Today Gen Forrest is reviled because of the Ft. Pillow incident...I hasitate to callit a massacre because I believe to a large extent it was media fueled propaganda, as well as for his supposed involvemnt with the KKK.
Neither of these incidents should detract from his record as a tactical genius and a superb leader whose men followed where ever he led.

Read about the Parker's Crossroads battle to get a good idea of his tactics... or Streight's Raid to see how he captured a force multiple times the size of his own or mamy many other exploits.